Numerical International Fixed Tropical Calendar

Courtesy: Wikipedia:

Most calendars have several rules which could be altered by reform:

• Whether and how days are grouped into subdivisions such as months and weeks, and days outside those subdivisions, if any.
• Which years are leap years and common years and how they differ.
• Numbering of years, selection of the epoch, and the issue of year zero.
• Start of the year (such as the December solstice, January 1, March 1, March equinox, Lady Day).
• If a week is retained, the start, length, and names of its days.
• Start of the day (midnight, sunrise, noon, or sunset).
• If months are retained, number, lengths, and names of months.
• Special days and periods (such as leap day or intercalary day).
• Alignment with social cycles.
• Alignment with astronomical cycles.
• Alignment with biological cycles.
• Literal notation of dates.

The Gregorian calendar is currently used by most of the world. There is also an international standard describing the calendar, ISO 8601, with some differences from traditional conceptions in many cultures.

Since the papal reform in 1582, several proposals have been offered to make the Gregorian calendar more useful or regular. Very few reforms have gained official acceptance. The rather different decimal French Republican Calendar was one such official reform, but was abolished twelve years later by Napoleon. After World War II, the newly formed United Nations continued efforts of its predecessor, the League of Nations, to establish the proposed World Calendar but postponed the issue after a veto from the government of the United States, which was mainly based upon concerns of religious groups about the proposed days that would be outside the seven-day week cycle ("blank days") and thus disrupt having a sabbath every seven days. Independently the World Council of Churches still tries to find a common rule for the date of Easter,^[5] which might be eased by a new common calendar.

Reformers cite several problems with the Gregorian calendar:

• It is not perennial. Each year starts on a different day of the week and calendars expire every year.
• It is difficult to determine the weekday of any given day of the year or month.
• Months are not equal in length, nor regularly distributed across the year, and so some people rely on mnemonics (e.g., "Thirty days hath September" or knuckle counting) to remember the lengths of months.
• The year's four quarters (of three full months each) are not equal (being of 90/91, 91, 92 and 92 days respectively). Business quarters that are equal would make accounting easier.
• Its epoch, i.e. start of the year count, is religious. The same applies to month and weekday names in many languages.
• Each month has no connection with the lunar phases.
• Solstices and equinoxes do not coincide with either the beginning of the Gregorian months or the midpoint of the months.
• The calendar does not have a year zero, the year after 1 BC was 1 AD, with nothing in between them.

It is hard or even impossible to solve all these issues in just one calendar.

International Fixed Calendar:

Advantages: 

The several advantages of the International Fixed Calendar are mainly related to its organization.

• The subdivision of the year is very regular and systematic:
  • Each month has exactly 4 weeks (28 days).
  • Every day of the month falls on the same weekday in each month (e.g. the 17th always falls on a Tuesday).
  • Every year has exactly 52 weeks divided in 13 months.
• The calendar is the same every year (perennial), unlike the annual Gregorian calendar, which differs from year to year. Hence, scheduling is easier for institutions and industries with extended production cycles.
• Movable holidays celebrated on the nth certain weekday of a month, such as U.S. Thanksgiving day, would be able to have a fixed date while keeping their traditional weekday.
• Statistical comparisons by months are more accurate, since all months contain exactly the same number of business days and weekends, likewise for comparisons by 13-week quarters.
• Supporters of the International Fixed Calendar have argued that thirteen equal divisions of the year are superior to twelve unequal divisions in terms of monthly cash flow in the economy.

Disadvantages

• While each quarter would be equal in length (13 weeks), thirteen is a prime number, thus placing all activities currently done on a quarterly basis out of alignment with the months.
• Christian, Islamic and Jewish leaders are historically opposed to the calendar, as their tradition of worshiping every seventh day would result in either the day of the week of worship changing from year to year, or eight days passing when Year Day or Leap Day occurs.
• The calendar disagrees with ISO 8601 regarding the first weekday of the week (Sunday vs. Monday), and major parts of the world would have to change what their first weekday of the week is.
• Birthdays, significant anniversaries, and other holidays would need to be recalculated as a result of a calendar reform, and would always be on the same day of the week. This could be problematic for public holidays that would fall on non-working days under the new system. For example, if a public holiday is celebrated on January 8, then under the International Fixed Calendar that holiday would always fall on a Sunday, which is already a non-working day, so compensatory leave would have to be given each year on January 9, which would essentially change the date of the holiday.
• A vast amount of administrative data (and the software that manages it) would have to be corrected/adjusted for the new system, potentially having to support both the IFC and the standard local time keeping systems for a period of time.
• Expiration dates on food items will have to be converted to the new calendar, and checking the dates to make sure the food is fresh could become harder and more confusing as a result, in the first couple years after the switch.

Revised International Fixed Calendar:

As per existing calendar, 365/366 days are reduced to 364 days calendar. remaining days of 1 or 2 will be blank days. This is not practically possible. So we keep extra days. International fixed calendar is modifiedas follows in two variations.

NIF Lemon(Numerical International Fixed Calendar):

1. All existing months of 30,31, days are replaced with unique 28 days. so we get the first 12 months of existing names with 28 days each. (Total 12x28=336 Days)

2. Last Month has 29 days in normal year and 30 days in leap year. This month is called as LEMON which is the abbreviation of LEap MONth.

3. Total calendar comes in single structure (January month is repeated for remaining 12 months.

NIF 2020:

SUN	MON	TUE	WED	THU	FRI	SAT
			1	2	3	4
5	6	7	8	9	10	11
12	13	14	15	16	17	18
19	20	21	22	23	24	25
26	27	28	29	30

 29, 30th day occurs only in Lemon. 

Lemon starts in Dec 3/2.

Lemon 29 equals to Dec 30. Lemon 30 equals to Dec 31

SI No	Month Name	Starting Gregorian Date in Normal Year	Starting Gregorian Date in Leap Year	Total Days / Month
1	January	Jan-01	Jan-01	28
2	February	Jan-29	Jan-29	28
3	March	Feb-26	Feb-26	28
4	April	Mar-26	Mar-25	28
5	May	Apr-23	Apr-22	28
6	June	May-21	May-20	28
7	July	Jun-18	Jun-17	28
8	August	Jul-16	Jul-15	28
9	September	Aug-13	Aug-12	28
10	October	Sep-10	Sep-11	28
11	November	Oct-08	Oct-07	28
12	December	Nov-05	Nov-04	28
13	Lemon	Dec-03	Dec-02	29/30*

4. week can be identified from date and month.

Total Days = 28*(M-1)+D

Week = [28*(M-1)+D]/7 = 4*(M-1)+(D/7)

5. Total Days between two dates in single year can be identified as follows.

M1,D1 and M2,D2;

TD = 28(M2-M1)+(D2-D1);

6. Existing Gregorian dates and International Dates are not synchronized from normal year and leap year.

ex: Mar 1 corresponds to New Mar 4 (Normal Year) and New Mar 5 (Leap year). So we can fix the dates 

NIF Midmo (Numerical International Fixed Calendar):

1. In NIF Lemon Calendar, All months are 28 days each. Last month has 29/30 days. The problem is this calendar not aligns with existing Gregorian calendar in the leap year. One day is shifted.
2. So we keep the second month 'February' as the leap month which has 28 days (Normal Year) and 29 days (Leap Year). This rule is same as existing rule.

2. A Intercalary Month of 28 Days is added between June and July (sol in existing international calendar). This month is called as MidMo which is the abbreviation of Middle Month.

3. Total calendar comes in single structure in Normal Year and Two month structure in Leap year.
Structure A: January and February

SUN	MON	TUE	WED	THU	FRI	SAT
			1	2	3	4
5	6	7	8	9	10	11
12	13	14	15	16	17	18
19	20	21	22	23	24	25
26	27	28	29 (February)

Structure B: March - December.

SUN	MON	TUE	WED	THU	FRI	SAT
				1	2	3
4	5	6	7	8	9	10
11	12	13	14	15	16	17
18	19	20	21	22	23	24
25	26	27	28	29(December)

SI No	Month Name	Starting Gregorian Date in Normal Year	Total Days / Month
1	January	Jan-01	28
2	February	Jan-29	28/29*
3	March	Feb-26/27	28
4	April	Mar-26	28
5	May	Apr-23	28
6	June	May-21	28
7	Midmo	Jun-18	28
8	July	Jul-16	28
9	August	Aug-13	28
10	September	Sep-10	28
11	October	Oct-08	28
12	November	Nov-05	28
13	December	Dec-03	29